Antennas used for mobile communications, satellite broadcasting and the like require a beam scanning function for enabling a beam direction change. As an antenna having such function, a scanned antenna that utilizes the large dielectric anisotropy (birefringence index) of a liquid crystal material (including nematic liquid crystals and polymer-dispersed liquid crystals) has been proposed (e.g., see Patent Documents 1 to 3). This type of scanned antenna is provided with a liquid crystal cell which includes a liquid crystal layer sandwiched between a pair of electrode-attached substrates.
The substrates are each formed with an alignment film covering electrodes on a surface on the side contacting the liquid crystal layer. The alignment film is made of a polymer material. During the production process for the liquid crystal cell, before the substrates are affixed to each other, the alignment film is subjected to a predetermined alignment treatment to exhibit a function for aligning the liquid crystal molecules in the liquid crystal layer in a predetermined direction.
When an alignment treatment (so-called photo-alignment treatment) is performed in which an alignment film is irradiated with light (for example, polarized ultraviolet light), a photoreactive polymer material is used in the alignment film. By irradiating the alignment film with light from the air interface side (front side), the polymer material is subjected to photoreaction.